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991.
The phase study of a Cd-Yb 1/1 approximant crystal over a wide pressure and temperature range is crucial for the comparison study between periodic and quasiperiodic crystals. The Cd(4) tetrahedra, the most inner part of the atomic clusters, exhibited various structural ordering in the orientation sensitive to pressure and temperature. Five ordered phases appeared in a P-T span up to 5.2 GPa and down to 10 K. The propagation direction of ordering alternated from [110] to <111> to at about 1.0 GPa and again to [110] at 3.5-4.3 GPa. The primarily ordered phases that appeared by cooling to 210-250 K between 1.0-5.2 GPa further transformed to finely ordered ones at 120-155 K. Besides the original short-range type interaction, a long-range type interaction was likely developed under pressure to lead to the primary ordering of Cd(4) tetrahedra. Coexistence of these interactions is responsible for the complicated phase behavior.  相似文献   
992.
Diffraction phase microscopy for quantifying cell structure and dynamics   总被引:2,自引:0,他引:2  
We have developed diffraction phase microscopy as a new technique for quantitative phase imaging of biological structures. The method combines the principles of common path interferometry and single-shot phase imaging and is characterized by subnanometer path-length stability and millisecond-scale acquisition time. The potential of the technique for quantifying nanoscale motions in live cells is demonstrated by experiments on red blood cells.  相似文献   
993.
Using a novel noncontact technique based on optical interferometry, we quantify the nanoscale thermal fluctuations of red blood cells (RBCs) and giant unilamellar vesicles (GUVs). The measurements reveal a nonvanishing tension coefficient for RBCs, which increases as cells transition from a discocytic shape to a spherical shape. The tension coefficient measured for GUVs is, however, a factor of 4-24 smaller. By contrast, the bending moduli for cells and vesicles have similar values. This is consistent with the cytoskeleton confinement model, in which the cytoskeleton inhibits membrane fluctuations [Gov et al., Phys. Rev. Lett. 90, 228101, (2003).  相似文献   
994.
Journal of Radioanalytical and Nuclear Chemistry - Sediment wastes generated from nuclear facilities often contain uranium and iron. From the viewpoint of reduction of environmental impact,...  相似文献   
995.
Journal of Thermal Analysis and Calorimetry - The formation mechanism of inclusion complex between (-)-epigallocatechin gallate (EGCg), which is the main catechin in tea leaves, or...  相似文献   
996.
Using high bandwidth resistance measurements, we study the single-shot response of tunnel junctions subjected to spin torque pulses. After the pulse onset, the switching proceeds by a ns-scale incubation delay during which the resistance is quiet, followed by a 400 ps transition terminated by a large ringing that is damped progressively. While the incubation delay fluctuates significantly, the resistance traces are reproducible once this delay is passed. After switching, the time-resolved resistance traces indicate micromagnetic configurations that are rather spatially coherent.  相似文献   
997.
998.
We propose a spectral-mode-splitting scheme and how it can be applied to CSRZ and CSRZ-DPSK signal formats, and show that it provides both accurate chromatic dispersion detection in CSRZ application and robustness against linear cross talk and nonlinear impairment in CSRZ-DPSK applications.  相似文献   
999.
Oscillations characterized by three incommensurate frequencies (three-dimensional torus of T3) appear in a model of a nonlinear optical resonator driven by a laser beam with transversally inhomogeneous identity distribution. Destruction of T3 leading to chaos occurs when a combination harmonic of two frequencies grows suddenly in the vicinity of the third frequency (and vice versa).  相似文献   
1000.
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